1. Field of the Invention
The present invention relates, in general, to valves, and in particular, to a valve for use with low-pressure inflation by a fluid such as, for example, air.
2. Description of Related Art
It is often desired to have a valve for allowing the inflation of a container or vessel such as a cargo dunnage air bag or an air mattress, etc. Air-filled cargo dunnage bags are often used to cushion and stabilize cargo during shipment, and, because it is desirable to minimize the weight of the cargo, the dunnage bags are constructed with very thin walls of plastic material. Such thin walls of plastic material are very susceptible to frictional “burning” if air is injected at high force through a valve into the vessel against the plastic material. Prior art air valves are known that have a spring-loaded valve stem in which the valve is opened by forcing air under pressure against a valve closure plate of the valve stem so as to operate in opposition to the spring-loaded valve stem and open the valve. Such prior art air valves are unsuitable for low-pressure inflation, which has difficulty in opening a spring-loaded valve stem. Other air valves are known that have a flap on the interior of the vessel that close against the valve bore to seal the valve. Such valves are undesirable in that a finger or other object must be inserted through the valve bore to open the flap in order to permit deflation, and the inflating air pressure must be sufficiently high to cause the flap to open. Still other air valves are known that do not have a valve stem but simply use a cap on the exterior of the vessel to seal the valve. Such cap-sealing air valves are undesirable in that they permit air to escape when inflation ceases and while the cap is being sealingly secured onto the valve.
It is therefore desirable to have a valve suitable for use with low-pressure inflation that does not have a flap within the interior of the vessel that seals the valve bore and that does not have a spring-loaded valve stem.
A preliminary patentability search in Class 441, Subclass 41; Class 5, Subclass 703; and Class 137, Subclasses 223, 230, 231, 228 and 234.5, produced the following patents, some of which may be relevant to the present invention: Walsh, U.S. Pat. No. 2,390,199 (issued Dec. 4, 1945); Russell, U.S. Pat. No. 2,772,692 (issued Dec. 4, 1956); Di Geambeardino et al., U.S. Pat. No. 2,804,085 (issued Aug. 27, 1957); Silverman et al., U.S. Pat. No. 2,824,570 (issued Feb. 25, 1958); Bogossian et al., U.S. Pat. No. 3,351,081 (issued Nov. 7, 1967); Bogossian et al., U.S. Pat. No. 3,590,851 (issued Jul. 6, 1971); Andreasson, U.S. Pat. No. 3,785,395 (issued Jan. 15, 1974); Sorensen, U.S. Pat. No. 3,983,907 (issued Oct. 5, 1976); Harrison et al., U.S. Pat. No. 4,529,167 (issued Jul. 16, 1985); Pestel, U.S. Pat. No. 6,089,251 (issued Jul. 18, 2000); Lung-Po, U.S. Pat. No. 6,138,711 (issued Oct. 31, 2000); Weinheimer et al., U.S. Pat. No. 6,460,560 (issued Oct. 8, 2002); Chaffee, U.S. Pat. No. 6,508,264 (issued Jan. 21, 2003); and Li, U.S. Pat. No. 6,622,749 (issued Sep. 23, 2003).
Walsh, U.S. Pat. No. 2,390,199, discloses an air valve having a threaded insert that is threadedly received inside a valve bore, and the insert moves downwardly against a rubber sealing ring to seal the valve bore.
Russell, U.S. Pat. No. 2,772,692, discloses an air valve having a threaded insert that is threadedly received inside a valve bore, and a rubber gasket of the insert moves upwardly against a valve seat to seal the valve bore.
Di Geambeardino et al., U.S. Pat. No. 2,804,085, and Silverman et al., U.S. Pat. No. 2,824,570, disclose a valve insert wherein an insert threadedly received within a valve body lifts from a valve seat to allow air to pass through holes in the insert and thereby flow through the valve.
Bogossian et al., U.S. Pat. No. 3,351,081, and Bogossian et al., U.S. Pat. No. 3,590,851, disclose a spring-loaded check valve in which a spring biases a valve insert so that an O-ring seals against a valve seat. The present invention has no such biasing spring.
Andreasson, U.S. Pat. No. 3,785,395, discloses a valve having a valve disc forced against a valve seat by internal pressure in a vessel. The present invention has no such valve disc forced against a valve seat by internal pressure within the vessel.
Sorensen, U.S. Pat. No. 3,983,907, discloses a valve insert threadedly received into a bore of a threaded valve body, and the valve insert opens the bore as the insert is screwed into the vessel. However, the insert is received into the bottom of the bore from inside the vessel rather than being received into the top of the bore.
Harrison et al., U.S. Pat. No. 4,529,167, discloses a threaded valve stem received within a threaded valve bore of a valve body. As the valve stem moves upward within the valve body, an O-ring gasket disengages from a valve seat, allowing air to flow from a vessel and through holes in the valve stem and then out an axial bore in the valve stem.
Pestel, U.S. Pat. No. 6,089,251, discloses a valve in which a clack seals against a valve seat from the underside.
Lung-Po, U.S. Pat. No. 6,138,711, discloses a valve in which a flap seals against the underside of a valve seat. The present invention has no such flap.
Weinheimer et al., U.S. Pat. No. 6,460,560, discloses a valve having an insert cap with a one-way sealing flapper on the underside of the cap. The present invention has no such flapper.
Chaffee, U.S. Pat. No. 6,508,264, discloses a valve having a self-sealing flexible diaphragm that seals the underside of the valve. The present invention has no such self-sealing flexible diaphragm that seals the underside of the valve.
Li, U.S. Pat. No. 6,622,749, discloses a valve with a spring-loaded insert that presses a valve cock against a valve seat. The present invention is not spring loaded.
Additionally, Langston, U.S. Pat. No. 5,111,838 (issued May 12, 1992), discloses a dunnage bag air valve and coupling in which a valve stem is spring-loaded to close the valve; and Krier et al., U.S. Pat. No. 5,082,244 (issued Jan. 21, 1992), discloses a cargo air bag inflation valve and inflator combination in which a valve stem is spring-loaded to close the valve.
None of these references, either singly or in combination, disclose or suggest the present invention.